Star Births &

the Skeleton of the Universe

Abel 2744 has been nicknamed Pandora’s Cluster because of the many different and strange phenomena that were unleashed by a huge collision that occurred over a period of 350 million years. A simultaneous pile-up between at least four separate clusters has produced strange effects that have never been seen together before.

“Careful imaging of the night sky reveals that most matter, under the action of gravity, is being concentrated into long strands: filamentary structures, forming a gigantic network throughout the universe. Composed of a skeleton of dark matter – which attracts much of the universe’s ordinary matter towards it – this “cosmic web” was first imaged in 2014.”

“The discovery offers a significant validation of galaxy-formation models of in the Universe. ‘Now we must verify that the discovery of Abell 2744’s missing baryons is applicable to the entire universe,’ says lead researcher Dominique Eckert. ‘This will consist of studying these filamentary regions in detail, and measuring their temperature distribution and the various atoms that compose them, in order to understand how many heavy elements there are in the universe.’ If the researchers can measure the atoms in these filaments, they will be able to estimate the number of heavy nuclei formed by stars since the beginning of the universe.

The ESA is now developing a new space telescope to further pursue this line of research, in which Switzerland and the researchers from UNIGE are especially involved. The telescope, named Athena, is expected to be operational in the mid-2020s.”

“Astronomers discovered a nest of monstrous baby galaxies 11.5 billion light-years away using the Atacama Large Millimeter/submillimeter Array (ALMA). The young galaxies seem to reside at the junction of gigantic filaments in a web of dark matter. These findings support the model that monstrous galaxies form in areas where dark matter is concentrated. And since modern large elliptical galaxies are simply monstrous galaxies which have mellowed with age, they too must have originated at nexuses in the large scale structure.”